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v6.9.4
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * INET		An implementation of the TCP/IP protocol suite for the LINUX
  4 *		operating system.  INET is implemented using the BSD Socket
  5 *		interface as the means of communication with the user level.
  6 *
  7 *		Generic INET6 transport hashtables
  8 *
  9 * Authors:	Lotsa people, from code originally in tcp, generalised here
 10 *		by Arnaldo Carvalho de Melo <acme@mandriva.com>
 11 */
 12
 13#include <linux/module.h>
 14#include <linux/random.h>
 15
 16#include <net/addrconf.h>
 17#include <net/hotdata.h>
 18#include <net/inet_connection_sock.h>
 19#include <net/inet_hashtables.h>
 20#include <net/inet6_hashtables.h>
 21#include <net/secure_seq.h>
 22#include <net/ip.h>
 23#include <net/sock_reuseport.h>
 24
 
 
 25u32 inet6_ehashfn(const struct net *net,
 26		  const struct in6_addr *laddr, const u16 lport,
 27		  const struct in6_addr *faddr, const __be16 fport)
 28{
 
 
 
 29	u32 lhash, fhash;
 30
 31	net_get_random_once(&inet6_ehash_secret, sizeof(inet6_ehash_secret));
 32	net_get_random_once(&tcp_ipv6_hash_secret, sizeof(tcp_ipv6_hash_secret));
 33
 34	lhash = (__force u32)laddr->s6_addr32[3];
 35	fhash = __ipv6_addr_jhash(faddr, tcp_ipv6_hash_secret);
 36
 37	return __inet6_ehashfn(lhash, lport, fhash, fport,
 38			       inet6_ehash_secret + net_hash_mix(net));
 39}
 40EXPORT_SYMBOL_GPL(inet6_ehashfn);
 41
 42/*
 43 * Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
 44 * we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
 45 *
 46 * The sockhash lock must be held as a reader here.
 47 */
 48struct sock *__inet6_lookup_established(struct net *net,
 49					struct inet_hashinfo *hashinfo,
 50					   const struct in6_addr *saddr,
 51					   const __be16 sport,
 52					   const struct in6_addr *daddr,
 53					   const u16 hnum,
 54					   const int dif, const int sdif)
 55{
 56	struct sock *sk;
 57	const struct hlist_nulls_node *node;
 58	const __portpair ports = INET_COMBINED_PORTS(sport, hnum);
 59	/* Optimize here for direct hit, only listening connections can
 60	 * have wildcards anyways.
 61	 */
 62	unsigned int hash = inet6_ehashfn(net, daddr, hnum, saddr, sport);
 63	unsigned int slot = hash & hashinfo->ehash_mask;
 64	struct inet_ehash_bucket *head = &hashinfo->ehash[slot];
 65
 66
 67begin:
 68	sk_nulls_for_each_rcu(sk, node, &head->chain) {
 69		if (sk->sk_hash != hash)
 70			continue;
 71		if (!inet6_match(net, sk, saddr, daddr, ports, dif, sdif))
 72			continue;
 73		if (unlikely(!refcount_inc_not_zero(&sk->sk_refcnt)))
 74			goto out;
 75
 76		if (unlikely(!inet6_match(net, sk, saddr, daddr, ports, dif, sdif))) {
 77			sock_gen_put(sk);
 78			goto begin;
 79		}
 80		goto found;
 81	}
 82	if (get_nulls_value(node) != slot)
 83		goto begin;
 84out:
 85	sk = NULL;
 86found:
 87	return sk;
 88}
 89EXPORT_SYMBOL(__inet6_lookup_established);
 90
 91static inline int compute_score(struct sock *sk, struct net *net,
 92				const unsigned short hnum,
 93				const struct in6_addr *daddr,
 94				const int dif, const int sdif)
 95{
 96	int score = -1;
 97
 98	if (net_eq(sock_net(sk), net) && inet_sk(sk)->inet_num == hnum &&
 99	    sk->sk_family == PF_INET6) {
100		if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
101			return -1;
102
103		if (!inet_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif))
104			return -1;
105
106		score =  sk->sk_bound_dev_if ? 2 : 1;
107		if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id())
108			score++;
109	}
110	return score;
111}
112
113/**
114 * inet6_lookup_reuseport() - execute reuseport logic on AF_INET6 socket if necessary.
115 * @net: network namespace.
116 * @sk: AF_INET6 socket, must be in TCP_LISTEN state for TCP or TCP_CLOSE for UDP.
117 * @skb: context for a potential SK_REUSEPORT program.
118 * @doff: header offset.
119 * @saddr: source address.
120 * @sport: source port.
121 * @daddr: destination address.
122 * @hnum: destination port in host byte order.
123 * @ehashfn: hash function used to generate the fallback hash.
124 *
125 * Return: NULL if sk doesn't have SO_REUSEPORT set, otherwise a pointer to
126 *         the selected sock or an error.
127 */
128struct sock *inet6_lookup_reuseport(struct net *net, struct sock *sk,
129				    struct sk_buff *skb, int doff,
130				    const struct in6_addr *saddr,
131				    __be16 sport,
132				    const struct in6_addr *daddr,
133				    unsigned short hnum,
134				    inet6_ehashfn_t *ehashfn)
135{
136	struct sock *reuse_sk = NULL;
137	u32 phash;
138
139	if (sk->sk_reuseport) {
140		phash = INDIRECT_CALL_INET(ehashfn, udp6_ehashfn, inet6_ehashfn,
141					   net, daddr, hnum, saddr, sport);
142		reuse_sk = reuseport_select_sock(sk, phash, skb, doff);
143	}
144	return reuse_sk;
145}
146EXPORT_SYMBOL_GPL(inet6_lookup_reuseport);
147
148/* called with rcu_read_lock() */
149static struct sock *inet6_lhash2_lookup(struct net *net,
150		struct inet_listen_hashbucket *ilb2,
151		struct sk_buff *skb, int doff,
152		const struct in6_addr *saddr,
153		const __be16 sport, const struct in6_addr *daddr,
154		const unsigned short hnum, const int dif, const int sdif)
155{
 
 
156	struct sock *sk, *result = NULL;
157	struct hlist_nulls_node *node;
158	int score, hiscore = 0;
159
160	sk_nulls_for_each_rcu(sk, node, &ilb2->nulls_head) {
161		score = compute_score(sk, net, hnum, daddr, dif, sdif);
 
 
162		if (score > hiscore) {
163			result = inet6_lookup_reuseport(net, sk, skb, doff,
164							saddr, sport, daddr, hnum, inet6_ehashfn);
165			if (result)
166				return result;
167
168			result = sk;
169			hiscore = score;
170		}
171	}
172
173	return result;
174}
175
176struct sock *inet6_lookup_run_sk_lookup(struct net *net,
177					int protocol,
178					struct sk_buff *skb, int doff,
179					const struct in6_addr *saddr,
180					const __be16 sport,
181					const struct in6_addr *daddr,
182					const u16 hnum, const int dif,
183					inet6_ehashfn_t *ehashfn)
184{
185	struct sock *sk, *reuse_sk;
186	bool no_reuseport;
187
188	no_reuseport = bpf_sk_lookup_run_v6(net, protocol, saddr, sport,
189					    daddr, hnum, dif, &sk);
 
 
 
190	if (no_reuseport || IS_ERR_OR_NULL(sk))
191		return sk;
192
193	reuse_sk = inet6_lookup_reuseport(net, sk, skb, doff,
194					  saddr, sport, daddr, hnum, ehashfn);
195	if (reuse_sk)
196		sk = reuse_sk;
197	return sk;
198}
199EXPORT_SYMBOL_GPL(inet6_lookup_run_sk_lookup);
200
201struct sock *inet6_lookup_listener(struct net *net,
202		struct inet_hashinfo *hashinfo,
203		struct sk_buff *skb, int doff,
204		const struct in6_addr *saddr,
205		const __be16 sport, const struct in6_addr *daddr,
206		const unsigned short hnum, const int dif, const int sdif)
207{
208	struct inet_listen_hashbucket *ilb2;
209	struct sock *result = NULL;
210	unsigned int hash2;
211
212	/* Lookup redirect from BPF */
213	if (static_branch_unlikely(&bpf_sk_lookup_enabled) &&
214	    hashinfo == net->ipv4.tcp_death_row.hashinfo) {
215		result = inet6_lookup_run_sk_lookup(net, IPPROTO_TCP, skb, doff,
216						    saddr, sport, daddr, hnum, dif,
217						    inet6_ehashfn);
218		if (result)
219			goto done;
220	}
221
222	hash2 = ipv6_portaddr_hash(net, daddr, hnum);
223	ilb2 = inet_lhash2_bucket(hashinfo, hash2);
224
225	result = inet6_lhash2_lookup(net, ilb2, skb, doff,
226				     saddr, sport, daddr, hnum,
227				     dif, sdif);
228	if (result)
229		goto done;
230
231	/* Lookup lhash2 with in6addr_any */
232	hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum);
233	ilb2 = inet_lhash2_bucket(hashinfo, hash2);
234
235	result = inet6_lhash2_lookup(net, ilb2, skb, doff,
236				     saddr, sport, &in6addr_any, hnum,
237				     dif, sdif);
238done:
239	if (IS_ERR(result))
240		return NULL;
241	return result;
242}
243EXPORT_SYMBOL_GPL(inet6_lookup_listener);
244
245struct sock *inet6_lookup(struct net *net, struct inet_hashinfo *hashinfo,
246			  struct sk_buff *skb, int doff,
247			  const struct in6_addr *saddr, const __be16 sport,
248			  const struct in6_addr *daddr, const __be16 dport,
249			  const int dif)
250{
251	struct sock *sk;
252	bool refcounted;
253
254	sk = __inet6_lookup(net, hashinfo, skb, doff, saddr, sport, daddr,
255			    ntohs(dport), dif, 0, &refcounted);
256	if (sk && !refcounted && !refcount_inc_not_zero(&sk->sk_refcnt))
257		sk = NULL;
258	return sk;
259}
260EXPORT_SYMBOL_GPL(inet6_lookup);
261
262static int __inet6_check_established(struct inet_timewait_death_row *death_row,
263				     struct sock *sk, const __u16 lport,
264				     struct inet_timewait_sock **twp)
265{
266	struct inet_hashinfo *hinfo = death_row->hashinfo;
267	struct inet_sock *inet = inet_sk(sk);
268	const struct in6_addr *daddr = &sk->sk_v6_rcv_saddr;
269	const struct in6_addr *saddr = &sk->sk_v6_daddr;
270	const int dif = sk->sk_bound_dev_if;
271	struct net *net = sock_net(sk);
272	const int sdif = l3mdev_master_ifindex_by_index(net, dif);
273	const __portpair ports = INET_COMBINED_PORTS(inet->inet_dport, lport);
274	const unsigned int hash = inet6_ehashfn(net, daddr, lport, saddr,
275						inet->inet_dport);
276	struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash);
277	spinlock_t *lock = inet_ehash_lockp(hinfo, hash);
278	struct sock *sk2;
279	const struct hlist_nulls_node *node;
280	struct inet_timewait_sock *tw = NULL;
281
282	spin_lock(lock);
283
284	sk_nulls_for_each(sk2, node, &head->chain) {
285		if (sk2->sk_hash != hash)
286			continue;
287
288		if (likely(inet6_match(net, sk2, saddr, daddr, ports,
289				       dif, sdif))) {
290			if (sk2->sk_state == TCP_TIME_WAIT) {
291				tw = inet_twsk(sk2);
292				if (twsk_unique(sk, sk2, twp))
293					break;
294			}
295			goto not_unique;
296		}
297	}
298
299	/* Must record num and sport now. Otherwise we will see
300	 * in hash table socket with a funny identity.
301	 */
302	inet->inet_num = lport;
303	inet->inet_sport = htons(lport);
304	sk->sk_hash = hash;
305	WARN_ON(!sk_unhashed(sk));
306	__sk_nulls_add_node_rcu(sk, &head->chain);
307	if (tw) {
308		sk_nulls_del_node_init_rcu((struct sock *)tw);
309		__NET_INC_STATS(net, LINUX_MIB_TIMEWAITRECYCLED);
310	}
311	spin_unlock(lock);
312	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
313
314	if (twp) {
315		*twp = tw;
316	} else if (tw) {
317		/* Silly. Should hash-dance instead... */
318		inet_twsk_deschedule_put(tw);
319	}
320	return 0;
321
322not_unique:
323	spin_unlock(lock);
324	return -EADDRNOTAVAIL;
325}
326
327static u64 inet6_sk_port_offset(const struct sock *sk)
328{
329	const struct inet_sock *inet = inet_sk(sk);
330
331	return secure_ipv6_port_ephemeral(sk->sk_v6_rcv_saddr.s6_addr32,
332					  sk->sk_v6_daddr.s6_addr32,
333					  inet->inet_dport);
334}
335
336int inet6_hash_connect(struct inet_timewait_death_row *death_row,
337		       struct sock *sk)
338{
339	u64 port_offset = 0;
340
341	if (!inet_sk(sk)->inet_num)
342		port_offset = inet6_sk_port_offset(sk);
343	return __inet_hash_connect(death_row, sk, port_offset,
344				   __inet6_check_established);
345}
346EXPORT_SYMBOL_GPL(inet6_hash_connect);
347
348int inet6_hash(struct sock *sk)
349{
350	int err = 0;
351
352	if (sk->sk_state != TCP_CLOSE)
 
353		err = __inet_hash(sk, NULL);
 
 
354
355	return err;
356}
357EXPORT_SYMBOL_GPL(inet6_hash);
v5.9
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 * INET		An implementation of the TCP/IP protocol suite for the LINUX
  4 *		operating system.  INET is implemented using the BSD Socket
  5 *		interface as the means of communication with the user level.
  6 *
  7 *		Generic INET6 transport hashtables
  8 *
  9 * Authors:	Lotsa people, from code originally in tcp, generalised here
 10 *		by Arnaldo Carvalho de Melo <acme@mandriva.com>
 11 */
 12
 13#include <linux/module.h>
 14#include <linux/random.h>
 15
 16#include <net/addrconf.h>
 
 17#include <net/inet_connection_sock.h>
 18#include <net/inet_hashtables.h>
 19#include <net/inet6_hashtables.h>
 20#include <net/secure_seq.h>
 21#include <net/ip.h>
 22#include <net/sock_reuseport.h>
 23
 24extern struct inet_hashinfo tcp_hashinfo;
 25
 26u32 inet6_ehashfn(const struct net *net,
 27		  const struct in6_addr *laddr, const u16 lport,
 28		  const struct in6_addr *faddr, const __be16 fport)
 29{
 30	static u32 inet6_ehash_secret __read_mostly;
 31	static u32 ipv6_hash_secret __read_mostly;
 32
 33	u32 lhash, fhash;
 34
 35	net_get_random_once(&inet6_ehash_secret, sizeof(inet6_ehash_secret));
 36	net_get_random_once(&ipv6_hash_secret, sizeof(ipv6_hash_secret));
 37
 38	lhash = (__force u32)laddr->s6_addr32[3];
 39	fhash = __ipv6_addr_jhash(faddr, ipv6_hash_secret);
 40
 41	return __inet6_ehashfn(lhash, lport, fhash, fport,
 42			       inet6_ehash_secret + net_hash_mix(net));
 43}
 
 44
 45/*
 46 * Sockets in TCP_CLOSE state are _always_ taken out of the hash, so
 47 * we need not check it for TCP lookups anymore, thanks Alexey. -DaveM
 48 *
 49 * The sockhash lock must be held as a reader here.
 50 */
 51struct sock *__inet6_lookup_established(struct net *net,
 52					struct inet_hashinfo *hashinfo,
 53					   const struct in6_addr *saddr,
 54					   const __be16 sport,
 55					   const struct in6_addr *daddr,
 56					   const u16 hnum,
 57					   const int dif, const int sdif)
 58{
 59	struct sock *sk;
 60	const struct hlist_nulls_node *node;
 61	const __portpair ports = INET_COMBINED_PORTS(sport, hnum);
 62	/* Optimize here for direct hit, only listening connections can
 63	 * have wildcards anyways.
 64	 */
 65	unsigned int hash = inet6_ehashfn(net, daddr, hnum, saddr, sport);
 66	unsigned int slot = hash & hashinfo->ehash_mask;
 67	struct inet_ehash_bucket *head = &hashinfo->ehash[slot];
 68
 69
 70begin:
 71	sk_nulls_for_each_rcu(sk, node, &head->chain) {
 72		if (sk->sk_hash != hash)
 73			continue;
 74		if (!INET6_MATCH(sk, net, saddr, daddr, ports, dif, sdif))
 75			continue;
 76		if (unlikely(!refcount_inc_not_zero(&sk->sk_refcnt)))
 77			goto out;
 78
 79		if (unlikely(!INET6_MATCH(sk, net, saddr, daddr, ports, dif, sdif))) {
 80			sock_gen_put(sk);
 81			goto begin;
 82		}
 83		goto found;
 84	}
 85	if (get_nulls_value(node) != slot)
 86		goto begin;
 87out:
 88	sk = NULL;
 89found:
 90	return sk;
 91}
 92EXPORT_SYMBOL(__inet6_lookup_established);
 93
 94static inline int compute_score(struct sock *sk, struct net *net,
 95				const unsigned short hnum,
 96				const struct in6_addr *daddr,
 97				const int dif, const int sdif, bool exact_dif)
 98{
 99	int score = -1;
100
101	if (net_eq(sock_net(sk), net) && inet_sk(sk)->inet_num == hnum &&
102	    sk->sk_family == PF_INET6) {
103		if (!ipv6_addr_equal(&sk->sk_v6_rcv_saddr, daddr))
104			return -1;
105
106		if (!inet_sk_bound_dev_eq(net, sk->sk_bound_dev_if, dif, sdif))
107			return -1;
108
109		score = 1;
110		if (READ_ONCE(sk->sk_incoming_cpu) == raw_smp_processor_id())
111			score++;
112	}
113	return score;
114}
115
116static inline struct sock *lookup_reuseport(struct net *net, struct sock *sk,
117					    struct sk_buff *skb, int doff,
118					    const struct in6_addr *saddr,
119					    __be16 sport,
120					    const struct in6_addr *daddr,
121					    unsigned short hnum)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
122{
123	struct sock *reuse_sk = NULL;
124	u32 phash;
125
126	if (sk->sk_reuseport) {
127		phash = inet6_ehashfn(net, daddr, hnum, saddr, sport);
 
128		reuse_sk = reuseport_select_sock(sk, phash, skb, doff);
129	}
130	return reuse_sk;
131}
 
132
133/* called with rcu_read_lock() */
134static struct sock *inet6_lhash2_lookup(struct net *net,
135		struct inet_listen_hashbucket *ilb2,
136		struct sk_buff *skb, int doff,
137		const struct in6_addr *saddr,
138		const __be16 sport, const struct in6_addr *daddr,
139		const unsigned short hnum, const int dif, const int sdif)
140{
141	bool exact_dif = inet6_exact_dif_match(net, skb);
142	struct inet_connection_sock *icsk;
143	struct sock *sk, *result = NULL;
 
144	int score, hiscore = 0;
145
146	inet_lhash2_for_each_icsk_rcu(icsk, &ilb2->head) {
147		sk = (struct sock *)icsk;
148		score = compute_score(sk, net, hnum, daddr, dif, sdif,
149				      exact_dif);
150		if (score > hiscore) {
151			result = lookup_reuseport(net, sk, skb, doff,
152						  saddr, sport, daddr, hnum);
153			if (result)
154				return result;
155
156			result = sk;
157			hiscore = score;
158		}
159	}
160
161	return result;
162}
163
164static inline struct sock *inet6_lookup_run_bpf(struct net *net,
165						struct inet_hashinfo *hashinfo,
166						struct sk_buff *skb, int doff,
167						const struct in6_addr *saddr,
168						const __be16 sport,
169						const struct in6_addr *daddr,
170						const u16 hnum)
 
171{
172	struct sock *sk, *reuse_sk;
173	bool no_reuseport;
174
175	if (hashinfo != &tcp_hashinfo)
176		return NULL; /* only TCP is supported */
177
178	no_reuseport = bpf_sk_lookup_run_v6(net, IPPROTO_TCP,
179					    saddr, sport, daddr, hnum, &sk);
180	if (no_reuseport || IS_ERR_OR_NULL(sk))
181		return sk;
182
183	reuse_sk = lookup_reuseport(net, sk, skb, doff, saddr, sport, daddr, hnum);
 
184	if (reuse_sk)
185		sk = reuse_sk;
186	return sk;
187}
 
188
189struct sock *inet6_lookup_listener(struct net *net,
190		struct inet_hashinfo *hashinfo,
191		struct sk_buff *skb, int doff,
192		const struct in6_addr *saddr,
193		const __be16 sport, const struct in6_addr *daddr,
194		const unsigned short hnum, const int dif, const int sdif)
195{
196	struct inet_listen_hashbucket *ilb2;
197	struct sock *result = NULL;
198	unsigned int hash2;
199
200	/* Lookup redirect from BPF */
201	if (static_branch_unlikely(&bpf_sk_lookup_enabled)) {
202		result = inet6_lookup_run_bpf(net, hashinfo, skb, doff,
203					      saddr, sport, daddr, hnum);
 
 
204		if (result)
205			goto done;
206	}
207
208	hash2 = ipv6_portaddr_hash(net, daddr, hnum);
209	ilb2 = inet_lhash2_bucket(hashinfo, hash2);
210
211	result = inet6_lhash2_lookup(net, ilb2, skb, doff,
212				     saddr, sport, daddr, hnum,
213				     dif, sdif);
214	if (result)
215		goto done;
216
217	/* Lookup lhash2 with in6addr_any */
218	hash2 = ipv6_portaddr_hash(net, &in6addr_any, hnum);
219	ilb2 = inet_lhash2_bucket(hashinfo, hash2);
220
221	result = inet6_lhash2_lookup(net, ilb2, skb, doff,
222				     saddr, sport, &in6addr_any, hnum,
223				     dif, sdif);
224done:
225	if (IS_ERR(result))
226		return NULL;
227	return result;
228}
229EXPORT_SYMBOL_GPL(inet6_lookup_listener);
230
231struct sock *inet6_lookup(struct net *net, struct inet_hashinfo *hashinfo,
232			  struct sk_buff *skb, int doff,
233			  const struct in6_addr *saddr, const __be16 sport,
234			  const struct in6_addr *daddr, const __be16 dport,
235			  const int dif)
236{
237	struct sock *sk;
238	bool refcounted;
239
240	sk = __inet6_lookup(net, hashinfo, skb, doff, saddr, sport, daddr,
241			    ntohs(dport), dif, 0, &refcounted);
242	if (sk && !refcounted && !refcount_inc_not_zero(&sk->sk_refcnt))
243		sk = NULL;
244	return sk;
245}
246EXPORT_SYMBOL_GPL(inet6_lookup);
247
248static int __inet6_check_established(struct inet_timewait_death_row *death_row,
249				     struct sock *sk, const __u16 lport,
250				     struct inet_timewait_sock **twp)
251{
252	struct inet_hashinfo *hinfo = death_row->hashinfo;
253	struct inet_sock *inet = inet_sk(sk);
254	const struct in6_addr *daddr = &sk->sk_v6_rcv_saddr;
255	const struct in6_addr *saddr = &sk->sk_v6_daddr;
256	const int dif = sk->sk_bound_dev_if;
257	struct net *net = sock_net(sk);
258	const int sdif = l3mdev_master_ifindex_by_index(net, dif);
259	const __portpair ports = INET_COMBINED_PORTS(inet->inet_dport, lport);
260	const unsigned int hash = inet6_ehashfn(net, daddr, lport, saddr,
261						inet->inet_dport);
262	struct inet_ehash_bucket *head = inet_ehash_bucket(hinfo, hash);
263	spinlock_t *lock = inet_ehash_lockp(hinfo, hash);
264	struct sock *sk2;
265	const struct hlist_nulls_node *node;
266	struct inet_timewait_sock *tw = NULL;
267
268	spin_lock(lock);
269
270	sk_nulls_for_each(sk2, node, &head->chain) {
271		if (sk2->sk_hash != hash)
272			continue;
273
274		if (likely(INET6_MATCH(sk2, net, saddr, daddr, ports,
275				       dif, sdif))) {
276			if (sk2->sk_state == TCP_TIME_WAIT) {
277				tw = inet_twsk(sk2);
278				if (twsk_unique(sk, sk2, twp))
279					break;
280			}
281			goto not_unique;
282		}
283	}
284
285	/* Must record num and sport now. Otherwise we will see
286	 * in hash table socket with a funny identity.
287	 */
288	inet->inet_num = lport;
289	inet->inet_sport = htons(lport);
290	sk->sk_hash = hash;
291	WARN_ON(!sk_unhashed(sk));
292	__sk_nulls_add_node_rcu(sk, &head->chain);
293	if (tw) {
294		sk_nulls_del_node_init_rcu((struct sock *)tw);
295		__NET_INC_STATS(net, LINUX_MIB_TIMEWAITRECYCLED);
296	}
297	spin_unlock(lock);
298	sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1);
299
300	if (twp) {
301		*twp = tw;
302	} else if (tw) {
303		/* Silly. Should hash-dance instead... */
304		inet_twsk_deschedule_put(tw);
305	}
306	return 0;
307
308not_unique:
309	spin_unlock(lock);
310	return -EADDRNOTAVAIL;
311}
312
313static u32 inet6_sk_port_offset(const struct sock *sk)
314{
315	const struct inet_sock *inet = inet_sk(sk);
316
317	return secure_ipv6_port_ephemeral(sk->sk_v6_rcv_saddr.s6_addr32,
318					  sk->sk_v6_daddr.s6_addr32,
319					  inet->inet_dport);
320}
321
322int inet6_hash_connect(struct inet_timewait_death_row *death_row,
323		       struct sock *sk)
324{
325	u32 port_offset = 0;
326
327	if (!inet_sk(sk)->inet_num)
328		port_offset = inet6_sk_port_offset(sk);
329	return __inet_hash_connect(death_row, sk, port_offset,
330				   __inet6_check_established);
331}
332EXPORT_SYMBOL_GPL(inet6_hash_connect);
333
334int inet6_hash(struct sock *sk)
335{
336	int err = 0;
337
338	if (sk->sk_state != TCP_CLOSE) {
339		local_bh_disable();
340		err = __inet_hash(sk, NULL);
341		local_bh_enable();
342	}
343
344	return err;
345}
346EXPORT_SYMBOL_GPL(inet6_hash);